1. Technical Field
The present invention relates to an output circuit, a semiconductor integrated circuit, a resonating device, an electronic device, a moving object, and the like.
2. Related Art
In recent years, there have been a large number of standards for performing serial communication at a high data rate. For example, PECL (Positive Emitter Coupled Logic), LVPECL (Low Voltage PECL) and the like have been used. There are also a large number of output circuits appropriate for these standards, which are used in integrated circuit devices (ICs) and the like. For example, PECL output circuits are used in integrated circuit devices including an oscillation circuit, and output a differential signal of PECL on the basis of an oscillation signal.
Generally, in the PECL output circuit, a bipolar type NPN transistor is used in an output transistor (see, for example, JP-A-2001-320267). The bipolar type transistor operates at high speed, and thus is suitable for high-speed serial transmission.
Such a PECL output circuit is required to be manufactured using a BiCMOS process. However, when a BiCMOS process is used, a process cost increases as compared with a MOS process, and as a result, the cost of the integrated circuit device itself including the PECL output circuit increases.
As disclosed in Specification of U.S. Patent Application Publication No. 2009/0140768, a MOS-type transistor is used as an output transistor (see, for example, FIG. 8B of Specification of U.S. Patent Application Publication No. 2009/0140768), and can be manufactured using a MOS process. However, when the MOS-type transistor is used, process variation (for example, approximately ±0.1 V) generally occurs in its threshold voltage. For this reason, it is difficult to adapt an output voltage of a PECL output circuit disclosed in Specification of U.S. Patent Application Publication No. 2009/0140768 to the standard of PECL.